反转字符串，使得新的字符串为原来字符串的逆序。

例如：输入“I love you!”，输出"!uoy evol I"

#include <iostream>
#include <assert.h>

using namespace std;

char* rvsString(char* str)
{
	assert(str != NULL);
	//头指针
	char* start = str;
	//尾指针
	char* end = str + strlen(str) - 1;
	char temp;

	while(start<end)
	{
		temp = *start;
		*start = *end;
		*end = temp;

		start++;
		end--;
	}
	return str;
}
int main()
{
	char str[] = "I love you!";
	cout<<str<<endl;
	rvsString(str);
	cout<<str<<endl;

	return 0;	
}